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Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance
Published on: May 2, 2018
Conjugative plasmid conferring resistance to olaquindox
Anders Hay Sørensen1, Lars Hestbjerg Hansen, Elsebetta Johannesen
1Department of General Microbiology, University of Copenhagen, 1307 Copenhagen K, Denmark.
Antimicrobial Agents and Chemotherapy
|January 25, 2003
Summary
A novel conjugative plasmid, pOLA52, was identified in E. coli from swine manure, conferring resistance to the antibiotic olaquindox. This plasmid also provides resistance to ampicillin and chloramphenicol, with high transfer rates.
Area of Science:
- Veterinary Microbiology
- Antimicrobial Resistance
- Molecular Biology
Background:
- Antibiotic growth promoters are widely used in livestock.
- Antimicrobial resistance is a growing global health concern.
- Escherichia coli is a common bacterium found in animal agriculture.
Purpose of the Study:
- To isolate and characterize a plasmid conferring resistance to olaquindox from swine manure.
- To determine the transfer frequency and resistance profile of the isolated plasmid.
Main Methods:
- Isolation of Escherichia coli from swine manure.
- Plasmid DNA extraction and characterization.
- Conjugation experiments to assess plasmid transfer.
- Antimicrobial susceptibility testing.
Main Results:
- A conjugative plasmid, named pOLA52, was successfully isolated.
- pOLA52 confers resistance to olaquindox, ampicillin, and chloramphenicol.
- The plasmid demonstrated a high frequency of transfer between E. coli strains.
Conclusions:
- Plasmid-borne resistance to the antibiotic growth promoter olaquindox has been demonstrated for the first time.
- The conjugative nature of pOLA52 suggests a potential mechanism for the spread of antimicrobial resistance in E. coli.
- This finding has implications for monitoring and controlling antimicrobial resistance in food-producing animals.
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